Appending to XML File

[Wesley008]

Hello, Alright. I'm having trouble appending my Data to a XML File.

First, I'm creating the XML File Here.

Public Sub xmlCreateAccount(ByVal ID As String, ByVal Username As String, ByVal Password As String, ByVal GUID As String, ByVal FirstName As String, ByVal LastName As String, ByVal BirthDate As String, ByVal PhoneNumber As String, ByVal xmlWriter As XmlTextWriter)
        With xmlWriter
            .WriteStartElement("Account")
            .WriteStartElement("AccountID")
            .WriteString(ID)
            .WriteEndElement()
            .WriteStartElement("Username")
            .WriteString(Username)
            .WriteEndElement()
            .WriteStartElement("Password")
            .WriteString(Password)
            .WriteEndElement()
            .WriteStartElement("GUID")
            .WriteString(GUID)
            .WriteEndElement()
            .WriteStartElement("FirstName")
            .WriteString(FirstName)
            .WriteEndElement()
            .WriteStartElement("LastName")
            .WriteString(LastName)
            .WriteEndElement()
            .WriteStartElement("BirthDate")
            .WriteString(BirthDate)
            .WriteEndElement()
            .WriteStartElement("PhoneNumber")
            .WriteString(PhoneNumber)
            .WriteEndElement()
            .WriteEndElement()
        End With
    End Sub

Then, I call it here:

Private Sub btnRegister_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnRegister.Click
        If IO.File.Exists(DataPath & "Accounts.xml") Then
            Dim xmlDoc As New Xml.XmlDocument()
            xmlDoc.Load(DataPath & "Accounts.xml")
        Else
            Dim xmlWriter As New Xml.XmlTextWriter(DataPath & "Accounts.xml", System.Text.Encoding.UTF8)
            Clipboard.SetText(sGUIDCode)
            xmlWriter.WriteStartDocument(True)
            xmlWriter.Formatting = Xml.Formatting.Indented
            xmlWriter.Indentation = 5
            xmlWriter.WriteStartElement("Accounts")
            xmlCreateAccount(1, txtUsername.Text, Crypt(txtPassword.Text), Crypt(sGUIDCode), txtFirstName.Text, txtLastName.Text, dtpBirthDate.Value.ToShortDateString, txtPhoneNumber.Text, xmlWriter) 'CALLED HERE
            xmlWriter.WriteEndElement()
            xmlWriter.WriteEndDocument()
            xmlWriter.Close()
        End If
        frmGUID.ShowDialog()
        Me.Close()
    End Sub

So now. How do I append another xmlCreateAccount(....) to my Already Made XML File without writing over whats already their? But I also want it to WRITE under the last xmlCreateAccount and Above the EndElement("Accounts")